<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <style>
        .file {
            position: relative;
            display: inline-block;
            background: #D0EEFF;
            border: 1px solid #99D3F5;
            border-radius: 4px;
            padding: 4px 12px;
            overflow: hidden;
            color: #1E88C7;
            text-decoration: none;
            text-indent: 0;
            line-height: 20px;
        }
        .file input {
            position: absolute;
            font-size: 100px;
            right: 0;
            top: 0;
            opacity: 0;
        }
        .file:hover {
            background: #AADFFD;
            border-color: #78C3F3;
            color: #004974;
            text-decoration: none;
        }
    </style>
</head>
<body>
<form id="fileform" action="{:U('Member/uploadImg')}" method="post" enctype="multipart/form-data">
    <a href="javascript:;" class="file">选择文件
        <input   id="file" name="file" type="file" onchange="document.getElementById('fileform').submit();">
    </a>
</form>

</body>
</html>